Opponents of the county-approved Dutra asphalt plant, including the City of Petaluma, presented their case in a San Francisco appellate court Tuesday morning, and now await a decision from the three-judge panel.

City Attorney Eric Danly said he argued several key issues to the presiding justices with the hope that at least one of the points would cause the panel to send the project back to the Sonoma County Board of Supervisors, which approved the plant in 2010. The appellate court has 90 days to deliver its ruling.

"The hope is that the current board of supervisors would give due consideration to these very important issues if the project is sent back to them," said Danly.

Requests for comment from Dutra spokesperson Aimi Dutra were not returned.

After the county approved the asphalt plant on 37 acres of land next to Shollenberger Park, local environmentalists and park supporters voiced concerns that the plant and resulting truck traffic would create excessive noise and air pollution. The Petaluma City Council also opposed the project because of its location just outside city limits, and called it a blight on the city's southern entrance to the town.

Together with environmental groups, the city filed a lawsuit against the county and Dutra to stop the plant, arguing that the environmental concerns weren't properly addressed. Dutra argued that the plant's environmental impacts were adequately mitigated, and touted the plant as a green facility that would save the city money on projects that require asphalt.

In December 2012, a Sonoma County judge dismissed the lawsuit, which sparked an appeal to the First District Court of Appeals in San Francisco. Opponents argued that the county improperly measured air pollutant emissions, illegally changed land-zoning designation to allow the plant and incorrectly categorized the business to allow for the zoning change. According to those present in court, the judges asked a multitude of questions of both sides.

"Hopefully, one of these arguments prevails," said Mayor David Glass, who attended the hearing with about 30 other Petaluma community members. "An asphalt plant at our gateway to Petaluma and the county does not serve tourism well. Our fate is in the hands of the appellate court. Personally, I've got to accept whatever the result is, but I feel good that we've done everything we can."

Joan Cooper of the community group Friends of Shollenberger, said she remains optimistic.

"We're very proud to know we've done all we can to protect Petaluma," she said.